An NYPD cop fatally shot himself last night while on-duty and interviewing the victim of a Queens car break-in, sources told The Post.

The officer, whose name was withheld pending family notification, got into a heated argument on his cellphone with his girlfriend and fired one bullet into his face after the conversation ended at around 11 p.m., the sources said.

The cop, a five-year veteran assigned to the 111th Precinct, went with his partner to a house on 211th Street near 85th Avenue in Hollis Hills to talk to a man whose car had been broken into Wednesday.

While interviewing the crime victim, the 28-year-old officer took the call and got into a shouting match, sources said.

He then took out his gun and fired.

His partner was in the home at the time and quickly rushed out after hearing the shot.

“Did he just shoot himself?” the cop asked the stunned civilian.

The officer was rushed to Long Island Jewish Hospital, where he died a short time later.

Neighbors described a chaotic scene soon after the shooting.

“I didn’t hear any shots, but I saw police everywhere,” said Tao Barzvi, a neighbor. “I saw a body on the floor from my window. He was’t moving.”

Another neighbor, who only identified herself as Carol, said, “I heard one shot. It sounded like a gunshot, but I’d never heard one before. The next thing, there were so many police officers.”